1. Field of the Invention
The invention relates to an electromagnetic actuator.
2. Background of the Invention
The current state of knowledge is as follows.
An electromagnetic actuator which defines the class is known from DE 11 2006 002 553 T5. This actuator comprises a stator housing with an armature which is constructed of a magnetically soft core and permanent magnet rings which surround the same radially, wherein these permanent magnet rings are arranged about the core of the armature with opposite magnetic polarity with respect to each other. The stator housing has multiple axially-spaced field coils which are functionally assigned to the permanent magnet rings and are arranged concentrically to the same, and which are connected in opposing polarity. When current is fed to the field coils, the armature moves in the axial direction of the stator housing, and the movement direction depends on the direction of current flow.
To manufacture such an armature, the permanent magnet rings are glued onto the armature. The difficult, and particularly unclean, manipulation of the glue is a disadvantage. As such, by way of example, excess glue must be scraped off, and in the process the danger exists that the excess glue can migrate to other parts of the actuator in an undesired manner.
In addition, it has been found that during operation of such an actuator, the danger exists that the armature can became tilted against the inner walls which form the armature space, when the armature is moved. In addition, it cannot be ruled out that the brittleness of the material of the permanent magnet rings used leads to wear on the inner walls of the armature space, or even to a break in the permanent magnets.
For this reason, the problem addressed by the invention is that of providing an electromagnetic actuator of the type named above, having improved properties, wherein the named disadvantages are particularly avoided.